JoJo's Bizarre Adventure detecting that my PS1 is modded?

Just got a modded PS1 to play region free games. Not sure which mod is in it.

A few games have worked fine but my copy of JoJo's Bizarre Adventure throws up this screen which I can't get out of after pressing start on the attract mode. It displays a loading screen for the main menu presumably and throws this up requiring a console reboot.

The Google translate app on my phone doesn't give great results but it thinks it is something about a modification. This is a legit copy of JoJo, is it detecting this is a modded machine?

Not all ‘stealth’ chips circumvent every protected game so a ‘stealth’ chip per se is incorrect. It should specifically be mayumi v4 / MM3 code to play everything.

Guess I should have specified that. I was getting at that having a machine modded with a contemporary solution rather than buying blind would be the way to go. I like the Mayumi V4 myself, feels slightly more integrated.

You can also try a boot disc called 'Import Player Light' which can easily be downloaded if you google it (v2.1 appears to be the last version released). Besides having antimod capability it can also run PAL games at 60hz and vice versa.